Agricultural equipment operates in dusty, dirty environments full of light fluffy dry crop material. This equipment is traditionally powered with internal combustion engines, usually diesel engines.
Government regulations have recently required the use of devices to treat engine exhaust gas (hereinafter after-treatment devices or ATDs) to remove residual pollutants from the raw exhaust gas. These devices can be remotely mounted from the engine to treat the exhaust gas. The ATDs have a very high surface temperature when they undergo periodic regeneration. These high temperatures at the outer surface of the devices can cause dust or other plant matter that collects on the outer surface to combust.
One way of preventing this combustion is to keep the surface of the ATD clean. This can be achieved by directing a portion of the air moved by the radiator cooling fan across the upper surface of the ATD. An example of this arrangement can be seen in US 2010/0275587 A1.
A drawback to these and similar designs is that the air used for cleaning the surface of the ATD contains dust and other plant matter. The air directed across the surface of the ATD by these prior designs must scour the surface at a high velocity in order to prevent the dust mixed with the air from settling on the surface of the ATD and permitting a layer of dust to build up.
Furthermore, if the ATD is placed remotely from the engine, a rather long conduit must be provided to conduct air from the cooling air fan to the ATD.
What is needed is an arrangement for keeping the ATD clean of dust and other particulate matter using a source of clean air or gas that avoids the expense of using a conduit and that does not rob some of the power from the cooling fan.
It is an object of this invention to provide such an arrangement.